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Destiny
 5 years ago
Marcus has 2 sisters.The sum of the girls' ages is 13.The product of their ages is 36.How old is each sister?
Destiny
 5 years ago
Marcus has 2 sisters.The sum of the girls' ages is 13.The product of their ages is 36.How old is each sister?

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Let the age of the sisters as a and b. then, a+b=13 and a*b=36 this implies a=13b. hence (13b)(b)=36. solve it then u get the answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Say one sister is Z and another sister is Y. You'd have to make a simultaneous equation, so it would be: Z+Y=13 ZY=36 You could solve it multiple ways, but the way I think is easiest would be substitution. Basically, if you used substitution, you would get Y=13Z (because you solved for Y). Then you'd take that answer (13Z) and substitute it for Y in the second equation. You'd then get: Z times (13Z) = 36. So then you would just solve.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Z*(13Z)=13ZZ^2. 13ZZ^2=36. Then you can factor I think. So: Z^2+13Z36=0 But we don't want a negative Z^2, so we have to flip all of the signs. Now we get: Z^213Z+36=0. Then factor. Because 13Z is negative and 36 is positive, you're going to have two negative answers in your factors. What two numbers multiply to 36 and add up to 13? 9 and 4. So Z can either equal 9 or 4, because you have to flip the signs. (And that should be apparent because you can't be a negative age.) So the sisters are aged 9 and 4. I hope that makes sense.. I haven't done that kind of equation in forever, but I think it's right.

destiny
 5 years ago
Best ResponseYou've already chosen the best response.0thy...me too this is for my daughter she is in 4 g and I'm out of school for over 30 years..lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes.sarahlynn is right. the answer should be 4 and 9 years old.

destiny
 5 years ago
Best ResponseYou've already chosen the best response.0thank you this is the Destiny so one is 9 and the other one is 4 because 9*4=36 and 4*9=36 right so this would be right!!!
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